KMOS News

Instrument Status

KMOS is operational with 23 arms. The telluric stardard is observed with arms #3, #12 and #18.

News

2019-05-10 KMOS is available for scientific operations with 23 arms as arm #14 is parked and in simulation.

2019-05-08 Arms 4 and 8 have been replaced. Unfortunatly during the verification activities Arm #14 showed a hard point in the stepping motor of the linear device. It has been parked and is currently in simulation. KMOS can operate with 23 arms till next intervation. Verification activoties are expected to be completed within May 10th

2019-04-19 KMOS is currently unavailable for science operations. Arm 8 is stuck and deployed in the field of view at its maximum linear extent. An emergincy intervation is foreseen to start on March 27th.

2018-10-01 Since September 26 Arm #4 started to fail in its movements. The linear motion is irregular showing lateral drifts when the arm is deployed in the FoV. For safety reasons, the arm is put in simulation and KMOS is available for Science Operations with 23 arms until an intervention can be planned.

2018-08-30 An excraordinary intervation, concluded on Aug 20, was necessary to replace a broken cold head in Spectrograph #3. Following the recommissioning KMOS is avalable for science since Aug 23. However the performances of spectrograph #2 are degraded with astigmatism along the spatial direction (slit width decreased from 13.5 px to 13.2 px) and spectral direction with and degraded resolution of ~10%. The former can be appreciated only under exceptional seeing conditions, when the Nyquist sampling is almost reached. In Specrograph #3 we register a ~10% improve of the spectral resolution

2018-08-09 Due to the failure of a cold head, KMOS experienced a warm up of all the spectrographs and of detector #3. An emergency intervention is already ongoing. As for the current plan, the recomissioning will start on Aug 23.

2018-05-30 The intervations on KMOS and following commissioning have been succesful: Arm 1 and 3 have been replaced and arm 17 fixed. KMOS is now available for Science Operations with all 24 ARMs

2018-05-15 An intervention just started on KMOS to maintain the cold heads and fix/replace the underperforming arms (namely arm #1, #3 and #17). According to the current schedule the recomissioning is foreseen to start on May 23.

2018-01-07 Since December a flux loss has been detected also for ARM #17. The loss depends on the rotator position, at ROT=240 it reaches ~50%. It is a loss of efficiency in the arm but it is calibrated with the internal flats interpolated to the rotator position (standard pipeline procedure). Therefore, we will leave the arm active until it shall be fixed during the next intervention planned in the second half of May 2018.

2017-11-14 Since October a flux loss up to ~40% happened in ARM #1. Such flux loss depends on the rotator direction and happens at ROT=0 and 15 deg if the instrument is moving from negative positions towards positive ones, and at ROT=-30 and -45 deg when moving in the opposite direction. The origin of the problem is most probably in some loose optical element within the arm itself. The arm will remain anyhow active during the rest of P100 unless it's movement results unreliable. An intervention is planned in P101 to replace both Arm 1 and 3.

2017-08-08 As a consequence of a power cut, the focus in Spectrograph 3 has changed: the line spread function has a FWHM ~15km/s narrower than before.

2017-07-04 As of P100, a new KARMA version is available (version 2.7). This should be used for the preparation of the KARMA set up files. The new KARMA version allows to allocate 2 arms to the same target, one at the Telescope at Science position and the other at the Telescope at Sky position. This strategy is useful, for example, if the number of targets is less than 24. It has the advantage that the target is observed continuously throughout the whole nodding cycle, thus optimizing the observing time at the telescope. If this strategy is used it should be stated in the Readme file

2017-06-12 In the period May 14-30 a dirt pattern appeared on the focal plane of detector #1. Most probably, it is a flake of paint that detached from the interior of the instrument and fell onto the detector focal plane. The position of the dirt pattern affects a small area and wavelength range in the IFUs #7 and #8, in particular the top left quadrant of IFU #7 and the top right quadrant of #8.

2017-01-25 No intervention is foreseen to fix/replace Arm #3 in the next period, therefore KMOS will be operative with 23 arms instead of 24 during P100. Arm #4 is used to observe telluric standards for spectrograph 1.

2017-01-09 Arm 3 is still in simulation and will remain in this state as soon as the instrument can be warmed up and the arm fixed/replaced. Even though the astrometry is indeed re-calibrated, Arm 3 is still showing vignetting on sky with such vignetting being dependent on the arm and rotator position. As before, the arm to take the telluric standard for spectrograph1 is #4.

2016-09-05 Arm 3 is experiecing again issues: bad precision in prositioning as before plus vignetting. These issues are under investigation and Arm 3 is set to simulation and the arm to take the telluric standard for spectrograph1 is now #4.

Since 2016-07-18, arm 3 is showing some problems. It had been set to simulation for a short period (25th July to 4th August) but is now working again, albeit with a higher uncertainty on the positioning (about 3 pixels). For that reason, the arm to take the telluric standard for spectrograph1, was changed from #3 to #4.

2015-12-11 Starting from P97, we have included the new keyword NCYCLES in the KMOS_spec_obs_freedither template that can be used to repeat the defined dither cycle including sky observations NCYCLES times. This allows i.e. to stay on a target and take NCYCLES observations, making the design of transit observations easier.

2015-12-10 Starting from P97, darks with DITs corresponding to science obersvations, will no longer be taken by default. The 60s darks, that are used by the pipeline for the bad pixel correction will still be taken on a daily basis. This new procedure allows to remove the constraints on the usable DITs making the design of OBs more flexible and time-efficient.

2015-06-11 A facebook group has been created to exchange ideas, methods, software on KMOS data reduction and analysis.

2015-03-04: After an intervention to upgrade all arms, KMOS was handed back to Science Operation for recommissioning and testing.

2015-01-22 Arm 2 was put in simulation

2014-12-02 Arm 19 was put into simulation

2014-11-21 Arm 8 was put into simulation.

2014-11-18 Arm 4 was put into simulation.

2014-10-06: Arm 5,6,7,and 16 have been replaced, Electronics of Arm4 were changed. All arms except 11 are back in operation.

2014-08-24: Arm 7 in simulation.

2014-08-07: Arm 15 has been recoverd and is back in operation.

2014-08-06: Arm 5 was put in simulation.

2014-05-31: Arm 15 was put in simulation.

2014-05-20: Arms 4 and 11 are temporarily out of operations.

2014-04-01: Arm 11 is back in operation.

2014-02-21: KMOS was successfully recommissioned after an intervention to lower the vibration and to repair the arms that were locked during the last months. Arm 11 is still not available, all other arms work well within the specifications.